sell out

British  

verb

1. Also (chiefly Brit): sell up.  to dispose of (supplies of something) completely by selling

2. informal (tr) to betray, esp through a secret agreement

3. informal (intr) to abandon one's principles, standards, etc

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noun

1. informal a performance for which all tickets are sold

2. a commercial success

3. informal a betrayal

4. informal a person who betrays their principles, standards, friends, etc

sell out Idioms  

1. Dispose of entirely by selling. For example, The rancher finally sold out to the oil company , or The tickets to the concert were sold out a month ago . [Late 1700s]

2. Betray one's cause or colleagues, as in He sold out to the other side . [ Slang ; late 1800s]

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Example Sentences

Alvarez & Marsal also noted that more biotechs are deciding to sell out rather than go public.

From Barron's • Apr. 6, 2026

AMC tries to make sure all its vessels sell out because it drives excitement among fans, Storm said.

From Los Angeles Times • Apr. 6, 2026

With every EFP round came fresh promises they would never sell out to "big beer".

From BBC • Mar. 6, 2026

Attendances at BKB venues are capped at 2,000 and the organisation's president David Tetreault says they generally sell out.

From BBC • Feb. 20, 2026

Indeed, it was largely ignored by most people at first—the original edition of 400 copies didn’t even sell out.

From "The Scientists" by John Gribbin